Machinery packing of the automatic type



Patented Noam 194i .loe H. Dnnlevy, PalmyragN. Y., assigner to TheGar-lock Packing Company, Palmyra, N. Y., a corporation of New YorkApplication .my s, 1941, sym No. 401,451

Claims.

t i This invention relates to machinery packing of vide an improvedpacking of the automatic type such thaty the elements of an assembly inwhich it is used will not be distorted or disarranged when subjected toextremely high pressures and thereby impair the seal. l

In the accompanying drawing illustrating two alternative, preferredforms of the invention- Figure l is a cross-sectional view of aconventional iorm of stuiilng-box'in which is installed a packingassembly including elements embodying one form ofthe invention.

Fig. 2 is a View, partly in cross section and partly in perspective,illustrating fragmentary portions of the packing elements, shown in Fig.1, as having been disassembled.

Fig. 3 is a cross-sectional view of a conventional stumng-box, such asis lllustrated'by Fig. l, in which is installed a packing assemblyincluding packing elements embodying an alternative, specic form of the.invention.

d is a View, partly in cross section an partly in perspective,illustrating fragments of packing elements such as are disclosed as apart of Flg. 3, the same having been disassembled.

Fig. 5 is a cross-sectional view of an assembly of automatic pacmngelements such` as are dis-` closed in the above-mentioned patent toHubbard et a1., the relative elements being represented as having beendistorted and displaced, as is likely to happen to such packing elementswhen subjected to excessively high pressures.

The automatic packing disclosed in the patent to Hubbard et al.,illustrated atically by Fig. 5 of the drawing of this application,comprised packing stock of relatively flat l V-shaped form in crosssection. rings 20 of which might be nested in an assembly as illustratedin Fig. 5, with their convex surfaces 2l nested ln concave surfaces 22of adjoining rings.

The concave surface portions. 22 of the rings 2% were grooved as at 28to provide zones 2l of reduced thickness adapted to serve as hinge-likeportions about which the outlying elements 2B might bel bent ordeflected outwardly so as to bring their sealingfsurfaces 2l into closecontact with the surfaces 2l of the piston and of the stuiling-box withwhich the packing was assoelated.

TEDSTATES PATENT OFFICE mommy rscxnvo or 'rua Au'rom'rro It was intendedthat the packing` of the prior art as illustrated. by Fig. 5 should beassembled ln the stuiilng-box with its outwardly inclined .surfaces 2land 22 directed towards the source of fluid pressure to be opposed, sothat the confined duid, when forced between the surfaces of the packingrings, would tend to iiatten them and thus force the outer portions intorm contact with the inner surface of the stufdng-box and the innerportions into rm contact with the' outer surface of the piston.

It will be apparent that when automatic packing such as that illustratedby Fig. 5 is used, the frictional engagement between the packing and thepiston, when the fluid pressure in the engine or pump with which thepacking is used lis increased to set the same inv operation,v will bemuch greater than it is when the duid pressure is reduced and the engineor pump permitted v to come to rest.

It has been found, as a result of long experience in the exploitation ofautomatic packlngs of the above-described character, that whenthey areusedas the sealing element of an engine or a pump or other mechanicalunit in which the fluid to be sealed must be subjected ,to extremelyhighpressures, the sealing effect of such packings, which is otherwisehighly satisfactory, is immired, for the reason that the protuberantportions 2@ of the packing rings are forced or wedged into the 'channelsor grooves 23 of ad- A joining rings, thereby causing the outlyingdaring elements to be distorted or disarranged so as to separateportionsof the rings adjacent their sealing surfaces and so as to alsoseparate the sealing surfaces from the walls of thetumngbox and piston,as indicated in Fig. 5 in which the disarrangement orv distortion isgrossly exag-l gerated for purposes of illustration.- 40 For theforegoing reasons it is an object of the present invention to producepacking stock including the automatically variable sealing propvertiesof the above-described packing of the prior art, but of relative formssuch as to' prevent the wedging action of one ring with respect to anadjoining ring when subjected to extremely high prelssu're so as toimpair the effectiveness of the sea The form of the herein-disclosedinvention -which is illustrated by Fig. 1 ls represented as a sealingagent' for a piston rod Il adapted to be reciprocated through aconventional stuffing-box 3i having the usual gland 32 and bolts I3 bywhich the gland may be caused to adjust the pressure of packing enclosedwithin the stuffing-box,

cave surface portion of the other end ring of the assembly of V-shapedrings, all in conformity with the assembly of packing elementsillustrated in Fig. 1 of the patent to Hubbard et al.

If the packingillustrated in Fig.y 1 is intended to prevent the escapeof fluids, such as a liquid or a gas maintained at a pressure materiallyabove atmospheric pressure, from the space 40 through the annular orice4| to the annular orifice 42 between the shaft and the gland of.

the stuling-box, the elements of the packing assembly will be mounted inthe stufng-box with their flaring surfaces positioned as shown, with theconcave surfaces directed towards the source of pressure. On the otherhand, if the packing is relied upon as a seal for a mechanical unit inwhich a vacuum is to be maintained, the positions of the elements of thepacking assembly should be reversed in order to prevent air fromentering the orice 42 between the cylinder and the gland of thestufiing-box and making its way to the orifice 4| through which it mightbe admitted to the vacuum'chamber.

In order that, when subjected to extremely high pressure, the packingelements of the form of the invention illustrated by Fig. 1 may not bedistorted or disarranged by the wedging of the protuberant portions 43of one ring into the opposed grooved portions 35 of another, in themanner in which the effectiveness of automatic packings of the prior artis sometimes impaired, there have been included, as important elementsof the herein-disclosed invention, intervening rings 44 ofcross-sectional forms such as to fill the grooves or channels 35 of theV-shaped rings and thereby prevent the protuberance of one ring frombeing forced into the channel in an adjoining ring.

The forms and dimensions of the V-shaped rings 34, the end adapter rings38, 39, and the filler rings 44, are to be such that the varioussurfaces which are mounted in opposition to one` another will be ofcomplelnental form such that the opposite surfaces of the V-shaped ringswill be incontinuous surfacetosurface contact from one sealing surfaceto the other.

In the alternative form of the invention illustrated by Figs. 3 and 4,the elements of the packing assembly diii'er from those of the assemblyillustrated as a part of Fig. 1 only in that the V-shaped packing rings|34 and the end adapter ring |39 are provided with integral, annular,protuberant portions |44 of cross-sectional forms and dimensionsconforming with those of the intervening rings 44 of the form of theinvention illustrated by Fig. l, so that the protuberances |44 may benested in the channels of the concave surface portions 36 of adjoiningrings.

In order that the V-shaped ring at the yleft end of the assemblyillustrated by Fig. 3 may be made of the same stock as is used in makingthe other V-shaped rings of the assembly, the end adapter ring |38 maybe channeled by a n groove |35 of a form such as to be complementary`with respect to the annular protuberant portion |44 of the adjoiningV-shaped ring.

Except as to the distinctive feature of the form of the inventionillustrated by Figs. 3 and 4 to which attention has been directed, theelements illustrated as parts of Figs. 3 and 4 conform exactly withthose illustrated as parts of Figs. 1 and 2; wherefore, suchcorresponding parts are designated by the same reference characters.

Although, for purposes of illustration, the herein-disclosed inventionhas been represented as one adapted to pack the joint about areciprocating piston, it will be apparent that it is not intended to belimited to any such special use as distinguished from the sealing ofjoints generally about rods, plungers, rotary shafts and the like, whichare subjected to liquid or fluid pressure..

The foregoing description and the drawing therein referred to are notintended to indicate that packings embodying the invention arenecessarily limited to elementsin the forms of continuous rings asdistinguished from rings having beveled ends or abutting ends, orring-like elements of packing applied in the form of a helix or spiral,in accordance with the well-known practice of the prior art. What is ofimportance is that the stock represented by the element |34, |44 ofFigs. 3 and 4 and the composite stock represented by the elements 34 and44 of Figs. 1 and 2, when assembled, shall be of forms such as toproduce packing elements having oppositely disposed surfaces which arecontinuously complementary from one marginal sealing surface to theother.

The various elements of the disclosed packing assembliesmay be made ofsoft metal, rubber composition or other appropriate material adapted tobe brought into a snug sealing contact with the surfaces against whichthey are intended to effect a seal, and they should also be ofappropriate material to withstand any damaging effect which might resultfrom contact with fluids or liquids to which they are exposed.

The invention is not intended to be limited to the specific forms hereindisclosed for purposes of illustration, but should be regarded asincluding modifications and variations thereof within the scope of theappended' claims.

What is claimed is:

l. A packing assembly comprising a plurality of interrelated, annularelements including rings of resilient material of relatively flatV-shaped crosssectional form each having a pair of oppositely disposedsealing surfaces connected by oppositely disposed surfaces, one convexand the other concave, of which the convex. surface portion of one maybe nested in the concave surface portion of another, the said ringsbeing channeled between their sealing surfaces by grooves, thecross-sectional forms and dimensions of the rings and their groovesbeing such as to materially reduce the thickness of annular portions ofthe said rings concentric with but lying at a distance from theirmargins and thereby adapt the portions thus thinned to serve ashinge-like connections for the oppositely related, outwardly flaringparts, and the various elements of the assembly being of forms anddimensions such that surface portions of each of the V- shaped ringswill make contact with complementary surface portions of other,adjoining elements continuously from one of its sealing surfaces to theother.

2. A packing assembly, conforming substantially with that defined byclaim 1, of which the interrelated, annular elements include ringsofspaces between the grooved surface portions of the channeled elementsand the opposed surface portions of adjoining elements.

3. A packing assembly, conforming substantially with that dened by claim1, of which each of the annular elements which is opposed by a groovedsurface portion of an adjoining elementis provided with an annularprotuberant portion of such form and dimensions that the opposed onesuch element may be nested in the concave surface portion of anadjoining one, said element being longitudinally channeled by a grooveextending along its concave surface portion and so dimensioned andpositioned as to materially reduce its thickns and thereby adapt theportion so thinned to serve as a hinge-like connection forthe oppositelyrelated, outwardly flaring parts, the other element of said two-partpacking unit the central part of its convex surface. portion, therelativ! cross-sectional forms 'of the two elements being such that whenassembled in either way the combined packing structure will haveoppositely disposed complementary surfaces extending continuously fromone of its sealing surfaces to thev other.

5. Resilient packing stock, of relatively flat, V-

shaped cross-sectional form, having oppositely disposed, longitudinalsealing surfaces connected by oppositely disposed longitudinal surfaces,one convex and the other concave, of forms such that the convex surfaceportion of one such element maybe nested in the concave surface portionof an adjoining one, said stock being longitudinally channeled by agroove extending along the central portion of its concave surface andhaving a protuberance extending lengthwise along the central portionof,its convex surface, the groove and protuberance being so disposed asto reduce the thickness of the stock along zones lying at materialdistances from its margins and thereby adapt the portionsthus thinned toserve as' hinge-like connections for the oppositely related. outwardlyflaring parts, and the relative forms of the concave portion includingits groove and 'the convex portion including its protuberance being ofcross-sectional form and dimensions l such that it may be used either asa ller for the groove of the V-shaped element, or as a cap for vface tothe other.

being such that surfaces of adjoining sections made from such stock willhave continuous com' plemental surface portions' from one sealing sur-JoE H. DUNLEVY.

